Mechanical stoker.



PATENTED JULY 7,1903.

E'.'F. EDGAR.

MECHANICAL STOKER.

APPLIOATION FILED JAN. 12, 1903.

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N0 MODEL.

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" in). 732,726.; PATENTBD JULY 7 190a.v

' 4E.P.EDGAR.

MEGHANIGAL STOKER.

APPLIOATION FILED JAN. 12, 1903.

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* UNITED STATES Patented'J'uly *7, 1903.

ELLIS F. EDGAR, OF WVOODBRIDGE, NEW JERSEY.

MECHANICAL STOKER.

SPECIFICATION forming part of Letters iatent No. 732,726, dated July 7, 1903. Application filed January 12, 1903; Serial No. 138,666. (No model.)

' To all whom it may concern.-

one of the grate-bar sections.

Beitknown that I,ELLIs F; -EDGAR;a citizen of the United States, and a resident of Woodbridge, in the county of Middlesex and State of New Jersey, have invented certain new and useful Improvements in Mechanical Stokers, of which the following is a specification.

Figure 1 is a vertical side view, part in full and part in section. Fig. 2 is a vertical front view in full. Fig. 3 is an enlarged vertical section view at lines 1 1 in Fig. 2. Fig. 4 is a plan view of one of the grate-bar sections. Fig. 5 is a side elevation view of Fig. 6 is a sectional view through two grate-bar axles and coupling-links at lines 6 6 in Fig. 7. Fig. 7 is a plan view of two grate-bar axles and coupling-links. Fig. 8 is a perspective view of one of the floor-sections of feed-hopper, Fig. 9 is an end view of one of the floor-sections of feed-hopper.

I had several objects in view in inventing this stoker-namely, a simple and durable construction as is possible to be obtained in a mechanical stoker, mechanism for operating the same on both sides to prevent side thrusts and uneven wearing of the bearings, and more perfect application of power and increase in economy by preventing loss of unburned coal.

1 represents ratchet or sprocket wheel, here shown as ratchet-wheelr This wheel is connected to a main power-shaft, a first link of connecting power to the stoker. 2 represents small gear-wheel connected to same axle, acting as second link of power, reducing the speed to gear-wheel; 3, third link of power, connected to gear-wheel; 4, fourth link of power, transmitting power to gear-wheels 7 7 with the aid of gear-wheel 8, operating-propellers 7 7, (shown in Fig. 3,) also operating gear-wheel 5, connected to driving-rod 12, connected to arm 13, operating plunger 25. The said gear wheel 4 also operates large gear-wheel 6, which is connected to the same axle and operates large power sprocket-wheel 30, (shown in Fig. 3,) which drives the endless traveling grate. 11 represents sides of stoker 5 21,back of hopper; l8, inclined front of hopper for throwing the coal to the back of hopper; 17, stationary grate at end of traveling grate for the reception of unburned coal from traveling grate; 15, idle sprocket-wheel for conveying grate-bar sections from upper track 31 to lower track 3l; -16, grate-bar sections;

23, axle extending the length of the gratebar sections, supporting and conveying said grate-bar sections on wheels 20, one of which is connected to each end of said axle23. Said axles 23 are held in position by coupling-links 6o 24, as shown in Figs. 6 and 7. 19 represents hand-wheel for raising or lowering false back 22 in hopper for varying the exit of hopper at plunger 25; 26, sectional bottom of hopper extending beyond hopper a short distance on the traveling grate-sections 16, blocks 27 and 28 for varying the height of the plunger 25, secured to plate 29, forming the top of plunger 25. i

Operation: Having placed coal in hopper 7o 32 and built fire on traveling grate composed of grate-bar sections 16,- also on. stationary grate 17, as soon as such fires are bright and part burned the stoker is set in operation by connecting up ratchet or sprocket wheel 1 to a power-shaft. The amount of coal desired to be fed through exit 33 by plunger 25 to the traveling grate is controlled by varying the heights of plugs 27 and 28 of plunger 25 and the raising and lowering of false back 22, and

by varying the length of strokc'of plunger 25 by moving the position of block 14 in the end of arm 13, secured to plate 29,'forming top of plunger 25, saidplug 14 may be moved and secured by tap-bolt, as'shown. here, or

may be secured and moved by a screw entering the end of slotted arm 13. The shorter and more frequent the strokes of plunger 25 the less liability of back-firing into hopper 32. The coal should be partially coked before leaving the sectional floor-plates 26 onto traveling-grate sections 16 t o prevent the loss of coal through the grate. The grate should travel at such a speed as to burn as much as possible of the coal before dumping on sta- 5 tionary grate 17 but not slow enough to cause holes through fire on said traveling grate or to have the fire thin enough to burn said traveling grate in furnaces of a very high temperature, caused by radiant heat from fire- Ico clay construction, which is advantageous in every way, provided the destruction of the grates is guarded against, as the higher the furnace temperature the better the results from the heating-surface of the boiler. The unburned coal and ashes that are dumped on stationary grate 17 should be occasionally spread over and leveled on said grate. Said grate should always be of a shaking type, so as to be shaken occasionally for removing the ashes to the ash-pit, and a traveling grate operated with this combination. The coal fired may be reduced to a fine ash without the loss of green coal or clinkers.

One of the very important features of this stoker is the construction of the travelinggrate sections and the manner of putting the same together and mounting it onthe small wheels, these grate-bar sections being composed of small grate-bar frames mounted on an axle having a small wheel at each end of said axle, said axle being placed as close as possible to the bottom of the grate-frames, as said axle forms the fulcrum as the wheels are carried around the ends of the tread on the sprocket-wheels. It is very important that the fulcrum be as near the grate-surface as possible to prevent the grates from parting and allowing the ashes to drop through. This is accomplished in this construction,which is quite clearly shown in the side elevation View of one of the sections in Fig. 5. The brickwork must be built out to overhang slightly the ends of the grate-bar sections to prevent coal from getting down on the wheels at the ends of the grate-bar sections. The stoker is so made to be withdrawn from the furnace, as it is mounted on wheels on a track for any repairs necessary. The end of the stationary grate is supported independently. The floorplates 26 are made narrow and have beads on the bottom, as shown in end view, Fig. 9, to allow the air to circulate between them and'the grate to prevent burning and warpin g.

Having thus described my invention, what I claim as new, and desire to secure by Letters Patent, is-

1. A mechanical stoker comprisinga traveling grate, a frame on which said grate is mounted, a fuel-feeding hopper at the forward end of the grate, a fuel-feeding plunger, a sectional floor for said plunger, one end of said floor being supported by the frame and resting upon the traveling grate, a stationary grate at the discharge end of the traveling grate, and operating mechanism for the traveling grate and plunger, substantially as set forth.

2. A mechanical stoker comprisinga traveling grate, a frame on which said grate is mounted, a fuel-feeding hopper at the forward end of the grate, a fuel-feeding plunger, a sectional floor on which said plunger operates, consisting of a series of bars or plates secured at one end to the frame and resting upon the grate, a rocking and dumping grate at the discharge end of the traveling grate, and operating mechanism on each side of thegrate-frame for operating the grate and the plunger, substantially as set forth.

3. A mechanical stoker comprising a traveling grate, a frame on which said grate is mounted, a fuel-feeding hopper at the forward end of the grate, a fuel-feeding plunger, a sectional fioor on which said plunger operates, consisting of a series of bars or plates provided with beads on their lower sides, said bars or plates being secured at one end to the frame and resting upon the traveling grate, a stationary grate at the discharge end of the traveling grate, and operating mechanism for the traveling grate and plunger, substantially as set forth.

4:. A mechanical stoker comprising a trav eling grate, a frame on which said grate is mounted, a fuel-feeding hopper at the forward end of the grate, a fuel-feeding plunger comprising a plate provided on its lower side with removable plugs or bars, a sectional floor on which said plunger operates, one end of said floor being supported by the frame and resting on the traveling grate, operating mechanism for the grate and the plunger, and means for varying the stroke of the plunger, substantially as set forth.

Signed at New York, in the county of New York and State of New York, this 10th day of January, A. D. 1903.

ELLIS F. EDGAR.

Witnesses:

O. B. GLIcK, G. E. LOTT. 

